diff options
Diffstat (limited to 'src/runtime/env_posix.go')
-rw-r--r-- | src/runtime/env_posix.go | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/src/runtime/env_posix.go b/src/runtime/env_posix.go new file mode 100644 index 0000000..0eb4f0d --- /dev/null +++ b/src/runtime/env_posix.go @@ -0,0 +1,70 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package runtime + +import "unsafe" + +func gogetenv(key string) string { + env := environ() + if env == nil { + throw("getenv before env init") + } + for _, s := range env { + if len(s) > len(key) && s[len(key)] == '=' && envKeyEqual(s[:len(key)], key) { + return s[len(key)+1:] + } + } + return "" +} + +// envKeyEqual reports whether a == b, with ASCII-only case insensitivity +// on Windows. The two strings must have the same length. +func envKeyEqual(a, b string) bool { + if GOOS == "windows" { // case insensitive + for i := 0; i < len(a); i++ { + ca, cb := a[i], b[i] + if ca == cb || lowerASCII(ca) == lowerASCII(cb) { + continue + } + return false + } + return true + } + return a == b +} + +func lowerASCII(c byte) byte { + if 'A' <= c && c <= 'Z' { + return c + ('a' - 'A') + } + return c +} + +var _cgo_setenv unsafe.Pointer // pointer to C function +var _cgo_unsetenv unsafe.Pointer // pointer to C function + +// Update the C environment if cgo is loaded. +func setenv_c(k string, v string) { + if _cgo_setenv == nil { + return + } + arg := [2]unsafe.Pointer{cstring(k), cstring(v)} + asmcgocall(_cgo_setenv, unsafe.Pointer(&arg)) +} + +// Update the C environment if cgo is loaded. +func unsetenv_c(k string) { + if _cgo_unsetenv == nil { + return + } + arg := [1]unsafe.Pointer{cstring(k)} + asmcgocall(_cgo_unsetenv, unsafe.Pointer(&arg)) +} + +func cstring(s string) unsafe.Pointer { + p := make([]byte, len(s)+1) + copy(p, s) + return unsafe.Pointer(&p[0]) +} |